Cultivator



April 1931- w. GRAMS 1,800,252

GULTIVATOR Original Filed Dec. 27, 1924 so cation an 40 when the s Patented Apr. 14, .1931

UNITED STATES PAiENT OFFICE WILHELK GRAHB, OI SYDOW'WIESE, GERMANY, ASSIGNOR TO BERTEL IBEITAG, Ii: .SCEEIN, OI VABCHIDT, mm KOBI-IN, GERMANY mnvaroa Original application filed December 27, 1824, Serial ll'o. 758,468, and in Germany larch 10, 1984. Divided and this application iiled'hnuary 19, 1928. Serial 10. 247,988.

My invention relates to cultivators, and has particular relation to the provision of means m connection with such apparatus as will in sure the roperoperation of the same when 6 various tructions, such as stones, etc., are encountered as the tools of the machine move over and through the surface of the ground.

Cultivators are at present used in which --'the tool shaft is rotating, to said shaft being I. seemed resiliently swingin tools. When anobstruction is encountere and a predetermined ressure is thereb exceeded at the point 0? the tool, the too s yield resiliently about their sus ension points and initiate a movement of the obstruction or stone forwardly in the direction that the tools move about their suspension points.

If coil springs are made to act on the tools, these s rings, which also serve as a link to pivotal and resiliently support the tools on the shaft, are distorted b the ressure exerted by the points of t e too upon the stones or other obstructions, radial forces acting on the springs, whereby the compressed steel fibres of the springs are liable to be overstrained and breakage of the ring may occur. It is therefore important t at means be provided whereby the coil springs (this term bein intended throughout this specifi-' the appended claims to include spiral springs of all kinds it being understood that such springs are arranged wlth their coils clear of obstructions, as and for the purpose described) on the shaft, such 35 springs are arranged with their axis substantially in parallel relation with the axis of the shaft, and the coils of the springs are clear of all adjacent parts so that they cannot get into frictional contact with such parts from, tension, whereby wear and eventual failure of the spring wire are prevented. Springs arranged with their coils clear of obstructions but in the usual manner, are dis- 0 torted by the pressure or tension exerted, are

a pair of end of rings are subjected to, or relieved.

nevertheless free to contract and expand substantially in their natural path.

This is obtained, accordm to the present invention, by providing an a utment for the top portion 0 the tool, so that this end of the tool is prevented from exerting any undue radial pressure on the spring or springs supporting the tool, such pressure being ta enup by the said abutment, which, in the preferred embodiment of my-1nvention, has the form of a crank arm fixed on the shaft, the free end of which extends into the axial line of the sup orting spring or s rings and has the top end of the tool hinge to it.

In the drawings aflixed to this specification and forming part thereof a device embodying my invention is illustrated diagrammatically by way of example.

In the drawings Figure 1 isia side elevational view showing the parts in their normal position.

Figure 2 is a similar view of the same parts after they have encountered an obstruction.

Fi 3 is a rear view,

Re erring to the drawings lis a tool shaft of a cultivator, 22, 23 and 24 are arms projecting for one side of the shaft and pitched apart axially as shown in Fig. 3, 7 is a pivot inserted in the central arm 23 in the axis of juxtaposed coil springs 11 the inner ends 12-12 of each spring being secured to the tool 3, as shown, while the outer ends 13-13 are secured to the arms 22 and 24 respectively, of the shaft '1. The

springs 11 thus support the tool the top 7 which is hinged to the crank arm at When the free end' 6 of the'tool encounters an ,obstruction, the ends 12 and 13 of each spring approach one another by describin approximately a circle about the pivot 7. ey cannot, however, depart radially from the circle because the pivot 7 abeorbs the excessive radial strains, and does an A said-shaft, said spring bemg not'yield when the point 6 of the tool strikes against a stone 8 and tends to rise.

Fig. 1 shows the tool 3 just before its end 6 strikes the stone 8 which is on the ground 15.

The line XX extending from the axis of the shaft 1 to the axis of the pivot 7 and the line w-b which extends from the end 6 of the tool 3 to the axis of the pivot 7, include an obtuse angle, in the initial position of the parts, with its apex in the pivot 7. The force which is exerted by the tool 3 tends to throw over the stone and the reaction tends to move the tool 3 out of the vertical position shown in Fig. 1 but due to the obtuse angle at the pivot 7 in combination with the rotary shaft 1, .the arm 23 does not move the tool out of its vertical position but only raises it as shown in Fig. 2. If the tool is not able to throw over the stone 8 by tilting it about its rear support on the ground 15, the tool rapidly rises further, while its end 6 slides across the stone while the obtuse angle illustrated in Fig. I is changed into a more acute angle by the 'force exerted at the shaft 1.

While I have described my invention in detail as to the actual construction employed, it is obvious that man modifications therein may occur to those skilled in the art, and I desire, therefore, that my invention be limited only by the sllOWlIlg of the prior art or by the scope of the appended claims.

1. A cultivator comprising a shaft,.a coil spring with its coils clear of obstructions,

and with its axis arranged substantially in parallel relation with respect to the axisof said shaft, said spring being connected with said shaft at one end, a tool connected with the other end of said spring, and an arm extending from said shaft to said toolso as to form an abutment for said tool and to prevent radial distortion of the free coils of said sprin when the end of said tool engages an o stacle.

2. A cultivator comprising a shaft, a coil spring with its coils clear of obstructions, and with its axis arranged substantially in arallel relation with respect to the axis of connected with said shaft at one end, a too connected with the other end of said spring, and an arm extending from said shaft to said tool, the free end of said arm being connected with said tool by a pivot so as to prevent radial distortion of the free coils of said spring when the end of said tool engages an obstacle.

3. A cultivator comprising a shaft, a coil spring with its coils clear of obstructions,

and with its axis arranged substantially in parallel relation with respect to the axis of said shaft, said springbeing connected with said shaft at one end, a tool connected with the other end of said spring, and an arm extending from said shaft to said tool, the free end of said arm being connected with said tool by a pivot in the axis of said spring so as to revent radial distortion of the free coils 0 said spring when the end of said tool engages an obstacle.

4. A cultivator comprising a shaft, two coil springs with their coils clear of obstructions and with their axes arranged substantially in parallel relation with respect to tially in parallel relation with respect to the axis of said shaft, said springs being connected with said shaft at one of their ends, a tool connected with the other ends of said springs, and an arm extending from said shaft to said tool, the free end of said arm being connected with said tool by a pivot, so as to prevent radial distortion of the free coils of said springs when said tool engages an obstacle.

- 6. A cultivator comprising a shaft, two coil springs with their coils clear of obstructions and with their axes arranged substantially in parallel relation with respect to the axis of said shaft, said springs being connected with said shaft at one of their ends, a tool connected with the other ends .of said springs, and an arm extending from said shaft to said tool, the free end of said arm being connected with said tool by a pivot in the axis of said springs, so as to prevent radial distortion of the free coils of said springs when said tool engages an obstacle.

7. A cultivator comprising a shaft, two coil springs with their coils clear of obstructions and with their axes arranged substantially in parallel relation with respect to the axis of said shaft, said springs being connected with said shaft at one of their ends. a tool connected with the other ends of said springs, and an arm extending from said shaft to being connected with said toolby a pivot in the axis of said springs, and centrally intermediate said springs, so as to prevent radial distortion of the free coils of said springs when said tool engages an obstacle.

8. A cultivator comprising a shaft, a coil spring with its coils clear of obstructions, and with its axis arranged substantially in parallel relation with respect to the axis of said shaft, said spring being connected with said shaft at one end, a tool connected with the other end of said spring, and an arm exsaid tool, the free end of said arm I tially tending from said shaft to said tool so as to form an abutment for said tool, with a line connecting the-axis of said spring with the axis of said shaft, and a line connecting the axis of said spring with the end of said tool, said lines including an obtuse angle the apex of which is in the axis of said spring, when said tool is in its initial position, so as to enable the end of said tool to move rapidly across an obstacle which it cannot remove.

9. A cultivator comprising a shaft, a coil spring with its coils clear of obstructions, and with its axis arranged substantially in parallel relation with respect to the axis of said shaft, said spring being connected with said shaft at one end, a tool connected with the other end of said spring, and an arm extending from said shaft to said tool, the free end of said arm being connected with said tool by -a. pivot, with a line connecting the axis of said pivot with the axis of said shaft, and a line connecting the axis of said pivot with the end of said tool, said lines including an obtuse angle the apex of which is in the axis of said pivot, when said tool is in its initial position so as to enable the end of said tool to move rapidly across an obstacle which it cannot remove.

10. A cultivator comprising a shaft, two coil springs with their coils clear of obstructions and with their axes arranged substanin parallel relation with respect to the axis of said shaft, said springs being connected with said shaft at one of their ends, a tool connected with the other ends of said springs, and an arm extending from said shaft to said tool so as to form an abutment for said tool with a line connecting the axis of said springs with the axis of said shaft, and a line connecting the axis of said springs with the end of said tool, said lines including an obtuse angle, the apex of which is in the axis of said springs, when said tool is in its initial position, so as to enable the end of said tool to move rapidly across an obstacle which it cannot remove.

11. A cultivator comprising a shaft, two coil springs with their coils clear of obstructions and with their axes arranged substantiall in parallel relation axis of said shaft, said springs being connected with said shaft at one of their ends a tool connected with the other ends of said springs, and an arm extendin from said shaft to said tool, the free end 0 said arm being connected with said tool by a pivot, with a line connecting the axis of said pivot with the axis of said shaft, and a line connecting the axis of said pivot with the end of said tool, said lines including an obtuse angle the apex of which is in the axis of said pivot, when said tool is in its initial position so as to en able the end of said tool to move rapidly across an obstacle which it cannot remove.

12. A cultivator comprising a shaft, a coil with respect to the spring with its coils clear of obstructions and with its axis arranged substantiallyin parallel relation with respect to the axis of said shaft, said spring being connected with said shaft at one end, a tool secured to the other end of said shaft, an arm extending from said shaft to said tool, a pivot connecting the free end of said arm and said tool in the axis of said spring, with a line connecting the axis of said pivot with the axis of said shaft, and a line connecting the axis of said pivot with the end of said tool, said lines including an obtuse angle the apex of which is in the axis of said pivot, when said tool is in its initial position so as to enable the end of said tool to move rapidly across an obstacle which it cannot remove.

13. A cultivator comprising a shaft, two coil springs with their coils clear of obstructions and with their axes arranged substantially in parallel relation with res act to the axis of said shaft, said springs emg connected with said shaft at one of their ends, a

tool connected with the other end of said spring, an-arm extending from said shaft to said tool, and a pivot connecting the free ends of said arm and said tool, said pivot being arranged centrally intermediate said springs, and in their axial line, with a line connecting the axis of said pivot with the axis of said shaft, and a line connecting the axisof said pivot with the end of said tool, said lines including an obtuse angle the apex of which is in the axis of said pivot, when said tool is in its initial position so as to enable the end of said tool to move rapidly across an obstacle which it cannot remove.

14. A cultivator comprisin a shaft, a. coil spring with its coils clear of o structions and with its axis arrangedsubstantially in parallel relation with respect to the axis of said shaft, said spring being connected with said shaft at one end, a tool connected with the other end of said spring, an arm on said tool, and an abutment on said shaft for the free end of said arm so as to revent radial distortion of the free coils 0 said spring when the end of said tool engages an obstacle.

15. A cultivator comprisin a shaft, a coil spring with its coils clear of o structionsand with its axis arranged substantially in anallel relation with respect to the axis 0 said shaft, said spring being connected with said shaft at one end, a tool connected with the other end of said spring, an arm on said tool, an arm on said shaft, and a pivot connecting said arms so as to revent radial distortion of the free coils 0 said sgring when the end of said tool engages an o stacle.

16. A cultivator comprisin a shaft, a coil spring with its coils clear of o structions and with its axis arranged substantially in parallel relation with respect to the axis of said shaft, said spring being connected with said shaft at one end, a tool connected with the other end of said'spring, an arm on said tool,

- said arms,

an arm on said shaft, and a pivot connecting with a line connecting the axis of said pivot with the axis of said shaft, and a line connecting the axis of said pivot with the end of said tool, said lines including an obtuse angle the apex of which is in the axis of said pivot, when said tool is in its imtial position soas to enable the end of said tool to move.

rapidly across an obstacle which it cannot remove.

In witness whereof, I have hereunto subscribed my name.

' WILHELM GRAMS. 

